/*
*
* Copyright 2008,2009 Newcastle University
*
* This file is part of Workcraft.
* 
* Workcraft is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
* 
* Workcraft is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
* GNU General Public License for more details.
* 
* You should have received a copy of the GNU General Public License
* along with Workcraft.  If not, see <http://www.gnu.org/licenses/>.
*
*/

package org.workcraft.history;
import java.util.List;

public interface HistoryProvider {
	public List<HistoryEvent> getHistory();

	public boolean canUndo();
	public void undo();
	public boolean canRedo();
	public void redo();

	public void moveToState (int index);
	public int getCurrentStateIndex();

	public void addHistoryListener(HistoryListener listener);
	public void removeHistoryListener(HistoryListener listener);
}